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authorEnric Balletbo i Serra <enric.balletbo@collabora.com>2017-06-27 12:27:24 +0200
committerJames Morris <james.l.morris@oracle.com>2017-07-07 09:49:26 +1000
commitb5d0ebc99bf5d0801a5ecbe958caa3d68b8eaee8 (patch)
tree82e09dabb210db95c61786f2dc981c616adeb12c /drivers/char/tpm
parent28707bf221ce6914a3e414637c8ffc4d27e9648d (diff)
tpm: do not suspend/resume if power stays on
The suspend/resume behavior of the TPM can be controlled by setting "powered-while-suspended" in the DTS. This is useful for the cases when hardware does not power-off the TPM. Signed-off-by: Sonny Rao <sonnyrao@chromium.org> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
Diffstat (limited to 'drivers/char/tpm')
-rw-r--r--drivers/char/tpm/tpm-interface.c3
-rw-r--r--drivers/char/tpm/tpm.h1
-rw-r--r--drivers/char/tpm/tpm_of.c3
3 files changed, 7 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 3123a6e44687..fe597e6c55c4 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -1119,6 +1119,9 @@ int tpm_pm_suspend(struct device *dev)
if (chip == NULL)
return -ENODEV;
+ if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
+ return 0;
+
if (chip->flags & TPM_CHIP_FLAG_TPM2) {
tpm2_shutdown(chip, TPM2_SU_STATE);
return 0;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 71d661a60df2..04fbff2edbf3 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -174,6 +174,7 @@ enum tpm_chip_flags {
TPM_CHIP_FLAG_IRQ = BIT(2),
TPM_CHIP_FLAG_VIRTUAL = BIT(3),
TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4),
+ TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5),
};
struct tpm_bios_log {
diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
index de57d4ac8901..aadb7f464076 100644
--- a/drivers/char/tpm/tpm_of.c
+++ b/drivers/char/tpm/tpm_of.c
@@ -36,6 +36,9 @@ int tpm_read_log_of(struct tpm_chip *chip)
else
return -ENODEV;
+ if (of_property_read_bool(np, "powered-while-suspended"))
+ chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
+
sizep = of_get_property(np, "linux,sml-size", NULL);
basep = of_get_property(np, "linux,sml-base", NULL);
if (sizep == NULL && basep == NULL)